Urinary Tract Infection
Urinary tract infections are common presentations to the family physician's office. It is important to delineate which UTIs are complicated, require further investigations, and management. History * Cystitis: dysuria, urgency, frequency, suprapubic pain/tenderness, new onset confusion * Urethritis: similar symptoms to cystitis - urethral d/c may be present * Pyelonephritis: cystitis symptoms, + systemic manifestations - fever, rigors, change in mental status, flank pain, costovertebral tenderness, hematuria, pelvic discomfort, N/V * Renal abscess: pyelo symptoms that persist despite abx * Past medical history: prior history of UTI, catheter, renal anomalies, immunosupression, history of incontinence, spinal cord injury, neuromuscular disorders, diabetes, renal stones * Medications: recent abx use * Allergies * Social history - including sexual history as STIs can present with similar Sx * Review of systems: vaginal symptoms, BMs * In a child < 3 years old with fever but no apparent source - suspect UTI * In elderly patients/young patients with non-specific complaints e.g. abdominal pain, fever, delirium, irritability, urinary retention, incontinence always consider UTI as part of the differential Risk factors * female, frequent sexual intercourse, catheter use, vesi-ureter reflux, posterior urethral valves, neurogenic bladder (e.g. spinal cord injury), diabetes mellitus, immunosuppresion , gyne prolapse, estrogen deficiency, benign prostate hyperplasia Common pathogens KEEPS # Klebsiella # E.coli # Enterococci # Proteus, pseudomonas # Staph saprophyticus Other: # Candida - common colonizer or urinary tract in hospitalized patients. Often does not require treatment # Staph aureus - always do blood cultures as uncommon in absence of catheter/instrumentation --> consider hematogenous spread # Urethritis: chlamydia, gonorrhea, trichomonas, HSV, ureaplasma, mycoplasma genitalium # Coagulase -negative staphylococcus (other than staph saprophyticus) rarely cause UTIs and generally do not require treatment Physical *Vitals *General *Abdominal exam - CVA tenderness, DRE (if thinking prostatitis) *+/- pelvic exam Investigations * NOT suggestive of UTI: 'foul smelling, cloudy urine, change in color, + urine dip without symptoms of UTI, pyuria/bacteriuria without signs/symptoms of UTI * Urinalysis and microscopy can rule '''OUT '''a UTI. Not rule in. Leuks - inflammation, Nitrites - presence of certain bacteria (not necessarily an infection). ** Nitrites can be falsely negative if frequent bladder emptying ** Nitrates negative in gram positive bug * If uncomplicated risk of UTI--> do scoring system ** 1 point for each - dysuria, leuks +, nitrites + ** 0-1 point --> send for culture ** 2-3 points--> start empiric therapy without waiting for culture * Investigations: ** Blood pressure ** Urinalysis ** Urine culture - clean catch, not toilet trained: urethral catheterization (NO urine bags) *** Sterile pyuria- can indicate urethritis, STI, nephritis, foreign body ** Cr, EGFR (if required for abx dosing, assess for acute kidney injury) ** Blood culture - complicated UTI or toxic appearing ** Chlaymdia/gonorrhea testing (see STI) if high risk ** Screen for asymptomatic bacteruia in all pregnant women and those undergoing urologic surgery ** Renal ultrasound +/- Voiding cystourethrogram *** Renal ultrasound: hydronephrosis, renal abscess, anatomic anomalies *** Voiding cystourethrogram: reflux (grading system - need for UTI prophlaxis and referral) **** First UTI in male **** First UTI in female < 3 years old or second UTI in female >3 years old **** Complicated pyelonephritis **** Family history of renal anomalies/recurrent UTIs esp. with HTN or poor growth **** Recurrent UTI ** CT renal: if no improvement in symptoms in 72 hours and want to r/o abscess, r/o struvite stone Classification Recurrent *Two uncomplicated UTIs within 6 months OR 3+ urine cultures within 12 months Reinfection *Occurs within 2 weeks of completing Abx (different organism) Relapse *Occurs within 2 weeks of completing Abx (original organism) Uncomplicated cystitis *cystitis in non-pregnant, non-immunocompromised host, without underlying structural/neurological d/o Complicated cystitis *structural/functional abnormalieis of renal system: obstruction (stones), catheter, spinal cord injury, neurogenic bladder, polycystic kidney disease *UTI in men *Pregnancy *Diabetes mellitus, immunosuprresion *Neonate Treatment * Treatment should only be considered if 1) signs and symptoms of UTI and 2) leuk esterase or WBC in urine +/- nitrates * Always consider local resistance patterns and patient's recent ABx use when prescribing * Aminoglycosides, cephalosporins, fluroquinolones and trimethoprim-sulfamethaxazole '''DO NOT COVER '''enterococcus * Ciprofloxacin and TMP-SMX do not reliably cover e.coli Asymptomatic bacteriuria *NO treatment even in catheter patients *'Exception: pregnant women, about to undergo urologic surgery Non-neuropenia Adult Patients without systemic signs/symptoms (no catheter) *Order urine R+M, C+S *Antibiotic options (tailor to culture susceptability) **Amox/clavulin 500mg PO TID or 875 mg PO q12 hours **Cephalexin 500mg PO q6 hours **Nitrofurantoin (Macrobid) 100mg PO BID **TMP-SMX 1 DS tab PO q12 hours **Ciprofloaxin 500mg PO q12 hours (reserve for severe or pseudomonal coverage) **Fosfomycin 3 grams dissolved in 1/2 cup water Po x 1 dose *Duration of therapy: **Risk factors (male, neurogenic bladder, immunosuppressive therapy, GU structural abnormalitiy e.g. non-obsturcting stone) --> Male 7 days, Other: 5-7 days for fluroquinolone, TMP/SMX, nitrofurantoin or 7-10 days with beta-lactam. Note '''some patients may require longer treatment **No risk factors: 3 days (fluroquinolone or TMP/SMX), 5-7 days (nitrofurantoin), 7 days (beta-lactam) *Adjustments: require renal adjustments. Do not rx nitrofurantoin if CrCl <60ml/minute Non-neutropenic Adult Patients with systemic signs/symptoms (no catheter) *Order blood cultures x 2, Urine R+M, C+S. *Antibiotic options **CiprofloxacinPO/IV q 12 hours **IV gentamycin 3mg/kg IV q 24 hours (tobra/amikacin) + ampicillin 1 gram IV q 6 hours **If CrCl < 40 ml/min or age >75 ceftraixone 1 gram IV q 24hours **If risk factors for pseudomonas: tobramycin 3mg/kg IV q24 hours '''or ceftazadine 1-2gram IV q8 hours or '''cipro *Duration of therapy: **Female: fluroquinolone (7 days), other (10-14 days) **Male: 10-14 days *Switch to PO: hemodynamicallys table, clinically improving, able to tolerate PO, functioning GI tract Catheter related UTI *Symptoms of rigors, delirium, new CVA tenderness, fever (cannot rely on dysuria, urgency, frequency) **None of the above--> no investigations, no treatment, look for alternative etiology, remove catheter if possible **Yes--> remove/change catheter, send urine R+M, C+S *If mild-moderate: (use different abx class than that used in last 3 months) **amoxicillin/clavulanic acid **Trimethoprim/sulfamethoxazole *If severe (draw blood cultures) **PO/IV cipro **IV gentamycin + ampicillin **If CrCl <40 or age > 75: ceftriaxone 1 gram IV q 24 **If suspect pseudomonas: tobramycin 3mg/kg IV q24 hours '''or ceftazadine 1-2gram IV q8 hours or 'cipro **Duration: 7 days if prompt response, 10 days if delayed *Tailor antibiotics to susceptability results. Switch from IV to PO when hemodynamically stable, improving clinically, able to tolerate PO, normal functioning GI tract Special Population Treatment Asymptomatic Bacterirua in Pregnancy *Screen at first prenatal visit. *Amoxicillin 500mg PO TID x 3-7 days. Other options: nitrofurantoin, TMP/SMX as long as no contraindications. *'Nitrofurantoin contraindicated in term pregnant woman (>36 weeks), labor, neonates due to risk of hemolytic anemia *'TMP/SMX is contraindicated in first trimester- risk of folate deficiency/NTD, and during last 6 weeks of pregnancy due to risk of kernicterus' *Perform follow-up culture and retreat if necessary Acute Cystitis in Pregnancy *Do follow-up culture to ensure resolution *Cephalexin 500mg PO TID-QID x 7 days *Other options: amoxicillin x 7days, nitrofurantoin x 5 days, fosfomycin x 1 dose , TMP/SMX x 3 days as long as no 'contraindications Pyelonephritis in Pregnancy *Ceftriaxone IV Early Recurrence <1 month: *re-treat x 7-14 days. Repeat culture. *Options: TMP/SMX, nitrofurantoin Prophylaxis *2 or more episodes in 6 months or > 3 episodes/year *First line: **TMP/SMX 1 tab or 1/2DS tab qhs 3x weekly or post-coital **Trimethoprim 100mg PO qhs or post-coital **Nitrofurantoin 50mg or 100mg qhs or post-coital *Second line: **Cephalexin 125-250mg qhs or post-coital **Norfloxacin 200mg PO every other day or 3x per week or post-coital **Fosfomycin 3 grams dissolved in 1/2 cup cold water q 10days Children First line *TMP/SMX 5-10mg/kg/day divided q12 hours *Nitrofurantoin 5-7mg/kg/day divided q6hours (DO NOT USE IN < 1 month old) Second line *Amoxicillin 40mg/kg/day divided q8 hours (high rate of resistance therefore need longer course) *Cephalexin 25-50mg/kg/day divided q6hours Third line *Cefixime 8mg/kg/day divided q12-24 hours *Amox/clav 40mg/kg/day divided BID Inpatient: IV amp/gent or ceftriaxone/cefotaxime *<2 months 5-7 days of IV treatment then PO x total 10-14 *PO cefixime *'Fluroquinolones are contraindicated in children < 12 years of age Prevention *Regular voiding patterns *Good hygiene practices *Remove catheter whenever it is contraindicated *Proper catheter maintenance practice (e.g. sterile insertion) Complications *sepsis *pyelonephritis *impacted infected stones *acute kidney injury Differential *See dysuria page *STIs, vaginitis, renal stones, interstitial cystitis, prostatitis Resources TOH guidelines for treatment of UTI Anti-infective Guidelines for Community Acquired Infections 2013